Process for alkali metal and quaternary nitrogen compound double salts of silicic acid

ABSTRACT

DOUBLE SILICATE SALTS OF ALKALI METALS AND QUATERNARY NITROGEN COMPOUNDS ARE PREPARED BY THE REACTION OF (A) AN ALKYLENE OXIDE, (B) AN AMINE, AND (C) AN ALKALI METAL SILICATE.

United States Patent Int. Cl. C07f 7/10 US. Cl. 260448.2 N 10 Claims ABSTRACT OF THE DISCLOSURE Double silicate salts of alkali metals and quaternary nitrogen compounds are prepared by the reaction of (a) an alkylene oxide, (b) an amine, and (c) an alkali metal silicate.

CROSS REFERENCE This application is a continuing application of my prior application, Ser. No. 614,027, filed Feb. 6, 1967, now abandoned, which in turn is a continuing application of Ser. No. 500,328, filed Oct. 21, 1965, now Pat. 3,383,- 386, which in turn is a continuing application of my prior Ser. No. 50,877, filed Aug. 22, 1960, now Pat. 3,239,549, which prior applications are hereby incorporated by reference in the present case.

THE INVENTION This invention broadly relates to a process for the production of crystalline quaternary nitrogen compounds having the general formula:

M X(N R O YSiO ZH O M preferably represents an alkali metal and most preferably sodium or potassium or mixtures thereof;

N represents a nitrogen atom;

11 indicates the number of nitrogen atoms and is a small integer, less than 10 and preferably less than five;

X, Y and Z represent numbers defining the relative amounts of each of the component parts of the compound. X is preferably between 0.5 and 1.5, Y is preferably between 2 and 10, and Z is preferably between 1 and 40, and wherein up to four R groups are associated with each N;

R represents an organic radical that forms with N an NR base selected from the group consisting of alkylamines, alkanolamines, heterocyclic amines and cyclic amines which produce solutions with a pH of at least 9;

, p is equal to the number of R groups and is at least 4 and up to 4n; s is an integer from 1 to p, indicating number of different types of R groups.

According to one specific embodiment the invention relates to a process for the production of compounds .having the formula:

M 0 X(NR R R R O -YSiO -ZH O wherein M, N, X, Y and Z have the significances noted above and R R R and R represent alkyl radicals containing between about 1 and 20 carbon atoms. Here p is 4 and s is 4 but may be any number from 1 to 4 inclusive.

In general, it can be said that the compounds of this invention are derived from nitrogen bases with a dissociation constant greater than that of NH (I6=1.8 10- pK=4.74) and/or nitrogen bases which produce solutions with a pH of at least 9.

In accordance with the process'of this invention, an alkylene oxide, e.g. ethylene oxide, is reacted with amines which in the presence of an alkali metal silicate will form quaternary ammonium ions corresponding to quaternary ammonium hydroxides, e.g. tetraethanolammonium hydroxide, tetrakis-2-hydroxyethyl piperazinium hydroxide, N,N-bis beta hydroxyethyl morpholinium hydroxide, N,N,N'-tris-(beta-hydroxyethyl)-N'-[tris (beta-hydroxyethyl) ethylammonium] piperazinium hydroxide. The alkali metal silicate acts both as catalyst and reactant to form the double salt. Any soluble alkali metal silicate may be employed.

The products of the reaction have been shown to be substantially independent of the SiO /Na O ratio of the soluble silicate used in the preparation. For instance, in the reaction between sodium silicate solutions, ethanolamine, and ethylene oxide, crystals were prepared using sodium silicate solutions varying in percent by weight ratio of SiO /Na O from 2.0'to 3.75. The final product varied in mol ratio over the following range:

It will be noted that the formulas have been shown in both the quaternary ammonium ion form and the equivalent quaternary ammonium oxide form with the ions shown by the cationic symbol For each mole of quaternary ammonium oxide there are two moles of quaternary ammonium cation. In some of these starting mixtures, potassium silicate was added to the sodium silicate without any essential change in the final product except that the alkali metal present was a mixture of sodium and potassium.

The reaction temperature has been varied from 25 C. to 150 C. but satisfactory products generally were not obtained at temperatures above about 100 C. Reaction time has been varied from 2 to 20 hours with some tendency for a lower ratio of the quaternary ion in the final product at the longer time limit.

For somewhat more complex derivatives I may react an alkylene oxide, such as ethylene oxide, with various amine compounds, whether primary, secondary or tertiary (such as triethanolamine, tetrahydroxyethyl ethylene diamine, ethylamine, monoisopropanolamine, morpholine,

various piperazine compounds, and various pyrrolidine compounds) and at the same time or subsequently reacting with an alkali metal silicate as a catalyst and/or re- 7 actant.

I reaction mixture is quite critical.

(3) The reaction temperature should be as low as possible, preferably room temperature or possibly lower. However, at temperatures much below room temperature,

. reaction time becomes unreasonably long.

(4) Small amounts of potassium salts increase the speed of crystallization considerably.

(5) The final solution supersaturates readily and therefore should be seeded and mechanical aids used for taste crystallization.

(6) Some soluble silica appears to be necessary as a 3 catalyst for the final step of the reaction to the quaternary form.

The ratio of silica to the combined alkali in the precipitated product can be increased by adding finely divided hydrated silica to the mixture. By this means the ratio of the SiO in the precipitate has been raised from about 3.3 up to 9 or even higher on the mol basis (i.e. 6.6 to 18 SiO :quaternary ammonium oxide). Mixtures of tetraethanolammonium hydroxide and alkali metal oxide in silicate solutions are also possible by these procedures: For instance, a solution formed by mixing S-35 sodium silicate with a solution of sodium tetraethanolammonium silicate will have an SiO :Na O ratio higher than that of S-35.

It should be noted here too that it is intended to include the intermediate solutions as part of this invention. They are used not only as a source of the quaternary ammonium silicate crystals, but may themselves be used in many of the same applications that will be described later. It is of particular importance that they represent solutions which may be raised to a very high ratio of silica to inorganic alkali and they may be concentrated to a rather high solids content. For instance, the following table shows Stormer viscosity in centipoises (cp.) at 20 C.

Solids content, percent by weight These aqueous solutions also readily dissolve finely divided silica, such as Bakers analyzed silicic acid, a hydrated xerogel, or Quso (sold by Philadelphia Quartz Company) which is a hydrated precipitated silica, or Syloid-308 which is a finely divided silica gel sold by Davison Chemical Co., or Hi-Sil X-303 which is a hydrated precipitated silica sold by Columbia-Southern Chemical Co. These all may be dissolved in the above solutions at room temperature (see Example 2). It was found that silica from silica gel dissolved in my sodium quaternary ammonium silicates is in a completely crystalloidal state, whereas such silica dissolved in a normal sodium silicate, such as N silicate, is in a completely colloidal state. The difference was demonstrated by the reaction with ammonium molybdate solution which with crystalloidal silica in my solution develops a yellow color whereas no color was found in the sodium silicate solution.

The reaction system for the preparation of these quaternary ammonium silicates involves a number of variables. First, there is the amine, ethylene oxide, an alkali silicate and water. In addition, the effects of temperature and time are important. Thus, I have found that because of the high solubility of most of these quaternary ammonium alkali metal silicate compounds, the solutions need to be concentrated a great deal to induce crystallization. Secondly, as indicated above, I have found that lower temperatures tend to promote the proper reaction and, in general, I propose to use temperatures below 100 C. and preferably about room temperature, although with some reactants it is necessary to carry out the preliminary steps at a higher temperature and in an autoclave. The effects of these variables have been outlined in general terms above and become more apparent in the following examples. It is to be noted also that the alkali metal silicate has a catalytic effect on the crystallization of the product and mixed alkali silicates seem to be even more effective as seen by the addition of small amounts of potassium silicate to reactions involving sodium silicate primarily.

The concentration of alkali metal silicate is also of great importance. Where a high concentration is present, the speed of crystallization is greatly reduced. Thus, when suflicient sodium silicate is present to bring about complete reaction of the ammonium compound, crystallization is quite slow. On the other hand, if rapid crystallization is to be attained, the concentration of the sodium silicate may be only 50% of that necessary for the complete reaction with the quaternary ammonium ion. The presence of a small amount of potassium silicate is helpful with these sodium silicate solutions when the maximum yield is desired.

PROPERTIES OF ALKALI METAL TETRAETHA- NOLAMMONIUM SILICATE CRYSTALS This crystalline compound has the approximate ratio of It crystallizes from water in pseudo-cubic crystals which are either monoclinic or triclinic in crystal character. They are anisotropic and thus birefringent and they are either uniaxial or biaxial. Their refractive indices were founsd 8to be alpha=l.498, beta=1.506, and gamma =1. 2

The crystals have a density at 20/20 of 1.604 and a melting point of 57-59 C. Softening begins at about 53 C. Solubility in water was found to be about 180 gms. in 100 ml. of water at 20 C. and 35.5 gms. in 100 ml. of water at 1.0 C. The crystals seem to be insoluble in all organic solvents. As indicated, the solubility rises rapidly as the temperature rises. Electrometric titration shows that this compound is a salt of a monobasic acid. It is either a double silicate salt or, if all the cationic groups can be combined as R 0, the ratio appears to be and the salt would be considered a disilicate. In the generalized formula p equals 4, s equals 1, n equals 1.

A second crystalline product has the ratio of IM OI 0.6N 4: 3.3SiO

(lM 0:0.3(N(C H OH) O:3.3SiO :8H O). It has a crystalline habit similar to the above-described silicate but a melting point at about 82-83 C. with softening beginning at 57 C. These crystals are also very soluble in water. When the cations are combined, the ratio appears to bfi lRgOIZ-SSlOzZ6HzO.

EXAMPLES A number of the materials used in the following examples are described as follows:

The alkali metal silicates, supplied by the Philadelphia Quartz Co., are:

Percent Ratio,

Trademark N820 Si On New 0 Hz 0 K20 Si 0: K20

Kasil #1 1:2. 50 8. 30 70. 5

Quso FF, a finely divided silica, also obtained as a trademarked product from the Philadelphia Quartz Company, has an ignited loss of 13.0%, with 7.2% of free water and 5.8% of bound water. It analyzed approximately 85% SiO with a surface area of about 280 mF/g.

Another form of silica was Sy1oid-308 supplied by the trademark owner Davison Chemical Company. This silica had an ignited loss of 4.0 and contained approximately SiO with a surface area of about 230 m. /g.

A finely divided silica Hi-Sil X-303, supplied by the trademark owner Columbia-Southern Chemical Company, had an ignited loss of 8.5% and contained approximately 89.4% SiO with a surface area of about m. /g.

' The ethylene oxide with a purity of about 99.5% was supplied by -MathesonCompany, Inc. H vEthanolamines were supplied by:' the Union Carbide Chemicals Co. as pure liquids. These were monoethanol- 6 I W Example2' v The solutions'of sodium tetraethanol-ammonium sili-' cate readily dissolve silicic acid in the'form ofhydrated silicas such as those already described.

1 Quat= quaternary.

zggg gf j ggg?g fi gg i i 5 For example, 50 parts sodium tetraethanolammonium Technical tetrahydroxy ethyl ethylene diamine was obe dlssolvFd 50 parts of water a 9' tained from Visco Products Co. 3 2 32 222 33122: fy z gz 24 parts a i p 1 ance,werep ce 1n a 5: 3 2? 83% ;22% 2??1 came from} Eastman the solution and revolved on a ball mill, most of the silica dissolved and the mixture set to a jelly-like material. 30 Analytical procedures parts additional of water were added and ball-milling continued. After 5 additional hours the mixture was m l e iiii i o ciiiir e iii i fiii ifi iisi i iffi f fi igiii g 5 g ffund .have 3 3 2 o a a o qua emary ions, 0 1 were used and are mcorporated herein by reference. the mol ratio was 2 O: 1. 4N 2 4 8.8 Si 2 Example 1 (1Na O:0.7(N(C H OH) O:8.8Si0g). A series of experiments set out in Table I was carried A Similar Solution wa q p y diss lving completeout with 60 parts of triethanolamine using 21 parts of 14 Parts of the e aeld- P had a ratlo of ethylene oxide in a closed autoclave at about 90 C. and 1Na20i1-4 qflatemafy 1011. and 75102 N 2 e 40 parts ethylene oxide in an open autoclave at the lower nary ammonium oxldeflslofl- The Solemn had a Sends temperatures. Specifically the triethanolamine and ethylcontent ene oxide were first dissolved in water and then the E A ee of 9 Parts 9 Sodlum tetraethallolammonisodium silicate was added with good agitation. A clear slheate was dlesolYed 111 Parts Of water containing solution was obtained. This was placed in an autoclave 2 l'esultmg a ratio of lNazoilAquateenary and heated at 80 to 100 C. for about five hours. No pres- 101123188102 (lNagoioj 'aa 2)- sure developed. A clear, yellowish solution was obtained, Suifielent finely dlvlded Q FF slllea was added to give and waterwas distilled from this solution at 40 C. bath a final of Nazoisloa of 114-2. After temperature and a reduced pressure f 25 to 0 mm Hg the ball mill at room temperature all of theBakersslhcrc into an ice-cooled receiver. After about 55% of the water acld the Q Q had ISSOIVed. When usmg Sylo d-308 had been removed, the solution was clear and showed no H1'S11 X-303 Place of Q1 9 1n Othel: t Was signs of coacervation. A solution of this concentration necessary f continue a ball mllllng Ovefnlght- Each of containing triethanolamine and sodium silicate always cothese Solutlons was clear to have a ratio of acervates. The solution was therefore placed in a refrigfl l a Y 2 2 quaternary er-ator and seeded with quaternary ammonium silicate ammonlum 9 2)- crystals. Within a few hours the crystals started to form The Solutlens were P e In a remgerawr SIX y and were filtered oif several days, washed with alcohol, at The w a P1:ee1P1tateS were then ether and dried in a vacuum The analysis f the crystal. lated by filtration and washing with alcohol and ether and line product and the yield is Shown in Table I. when the drying 1n vacuo as usual. The final product had a ratio of mother liquor was diluted with 1 part of ethanol to 7 parts 40 z quaternary Q 2 2 z of the liquor and placed back'in the refrigerator, addiquaternary ammemum 2= z tional crystals were b i d Similar reaction mixtures have been prepared and the The same process was carried out for reaction No. 2 in Pmdllet formed by Spray drying the Solution instead of the reaction time was only two hours allowing it to crystallize in a cake. In this way, the neces- A similar reaction was carried out using 8-35 and D y of grinding the Cake s a d.

sodium silicate instead of E and crystallized tetraethanol- In one such case the amount of dilution Water was a moni ilicat wer obt ined, sharply reduced to 60 parts in the formula given above. I In reaction No. 3 the mixture of E sodium silicate, The preparation and crystallization of this mixture was Kasil #1, potassium silicate, water, triethanolamine and carried out satisfactorily and the mass was spray dried ethylene oxide was heated for 20 hours at 70 in an auto-. using a ring type nozzle with six openings around the cenelave- The reaction P Qduet was a clear, eolel'less, Odofter, placed at the top of a 3 foot-2 inch conventional spray less solution. After the 97% of the additional water was (A fl id atomizing research type Spray dryer f removed, the solution was refrigerated and within a day the Swanson Corp. f Harvey, 11L) Best results were a large amount of crystals had formed. These were treated tained with an air inlet temperature of C. and as N 4 th d an outlet temperature of 80-90 C. The atomizing air 1s product was clear, colorless, and odorless, and after 97% 3 of gif fig ggg g g fi ggg 323 3 of the water had been evaporated the solution was again 65 t t th I 1 2 2 refrigerated and the crystals separated and treated as be- 2 e me am ammomum fore. At room temperature the yield was much higher than at the higher temperature. oxide:3.9SiO 3.3 H 0) TABLE I [Na-TEA silicates with a ration! M10 :N (C2H4OH)4:SiO2:HzO :1:1.4:3.8:11]

Composition of starting mixture, parts by wt; Yield, percent Analysis, percent by wt. Molar ratio of Naa0+K2O=1 7 Read Reac- Reaction tion Based Quatertion Kasil temp., time, Based on E.O. nary No. E #1 H1O C. hrs. on SiOz or amine Quat Hi0 SiOz NazO K20 (.Luai; 810: H1O oxide 1 120 320 90 5 12.4 6.2 35.22 25.11 30. 8.24 1.4 as 10.5 0.7 2 120 320 '90 2 26.5 12.7 33.17 29.02 29. 49 s. 12 1.3 3.8 12.3 0.65 3 228 16 300 20 24.9 a1. a 4 22s 16 300 25-30 19 31.3 29 2 a2. 67 28. st 29. 50 8.32 0. 2a 1.2 2 a 6 11.7 0.0

The lower water content is probably related to the higher melting point which was found to be 108 C. The product decomposed at 173 C.

Example 3 (1Na O:0.75 quaternary ammonium oxide:8.8SiO and contained 67.1% H 0. The Stormer viscosity at 20 C. was 62.7 sec.

Example 4 A number of quaternary ammonium compounds more complex that the tetraethanolammonium hydroxide may be used to react with dispersions of silica gel or solutions of soluble alkali silicate to form complex organic silicates in which all of the sodium is displaced. It is possible, for instance, to use 150 parts E silicate, 300 parts water, and 60 parts of tetrahydroxy ethyl ethylenediamine in solution. The clear solution obtained from this mixture was poured into a vessel equipped with a stirrer, a thermometer, a gas inlet tube, and a low temperature reflux condenser. 23 parts of ethylene oxide was added slowly through the gas inlet tube while the mixture was stirred vigorously. The exothermic reaction made it necessary to cool the reaction vessel to hold the temperature between 25 and 30 C. to obtain the maximum yield. After 12 minutes the temperature was 28 C., no refluxing was occurring but the vessel was cooled. After 24 minutes the temperature was still 27' C. and the solution was somewhat more hazy. By 30 minutes all of the ethylene oxide had passed over and the temperature was 26 C. The solution was clear in 2.5 hours, and at 6 hours 14 minutes the temperature was still 25 .5 C. with no odor of ethylene oxide. Ninety-six percent of the 300 parts water were distilled away leaving a viscous turbid solution which separated into two layers when left in the refrigerator at 2 C. Thirty parts water were added again which allowed the mixture to form a homogeneous solution and on refrigeration cube-like crystals of sodium hexahydroxyethyl ethylene diammonium silicate formed slowly.

Example It is evident that this reaction can be carried out with ethylene oxide and any of the other water miscible amines. For instance, in one reaction 140 parts of 13. sodium silicate was diluted with 300 parts of water and parts ethylamine was added. Thirty-two parts of ethylene oxide was allowed to run into the reaction flask with the temperature controlled as usual. It was noteworthy that during this reaction no coacervate formed and when the reaction was complete, 295 parts of water was distilled off. It was found that on cooling, two layers appeared and it was necessary to return parts of water to the solution, after which crystals formed slowly on standing.

Example 6 Monoisopropanolamine will react with ethylene oxide in this reaction. For instance, a mixture of 30 parts of monoisopropanolamine was dissolved in 3,00 parts of water and 228 parts of E sodium silicate. To this was added 16 parts of Kasil #1 potassium silicate and the reaction was carried out as before in the flask at about -30 C. The 53 parts of ethylene oxide were added slowly with=coo1ing of the reaction'mixture. .No refluxing occurred, but after about a half hour, aheavy coacervate formed. ,The ethylene oxide was added in the course of about one hour and in about six hours all the coacervate had dissolved. No ethylene oxide odor could be detected after standing overnight and then 189 parts ofwater. weredistilled off, leaving a clear solution. It was necessary to return 20 parts of water to maintain a single homogeneous solution in the refrigerator at 2 C.

Similarly, a solution may be formed by the reaction be: tween propylene oxide and. triisopropanolamine. -In this case, 76.5 parts of triisopropanolamine were mixed with 600 parts of water and parts of E sodium silicate, forming a clear solution to which the propylene oxide 'was added drop-wise at room temperature. A large amount of coacervate formed in the mixture overnight and it was necessary to continue the reaction much longer since the propylene oxide could still be detected.

Example 7 A sodium N,N bis-beta-hydroxyethylmorpholinium silicate may be formed by the reaction of ethylene oxide with morpholine. In the presence of the alkali silicate, the ethylene oxide adds to the imine group forming two ethanol side chains. This is a tetraethanolammonium hydroxide in which two OH groups have condensed with the loss of water, forming a morpholine ring.

In this case, 114 parts of E. sodium silicate were mixed with 8 parts of Kasil #1 potassium silicate in 300 parts of water and 35 parts of morpholine. This formed a clear solution and reaction started at 24 C. Cooling was started after 9 minutes when the temperature reached 28 C. and coacervation started at about 14 minutes and 30 C. In 35 minutes, all of the ethylene oxide had been passed into the solution and the temperature was 26.5 C. No refluxing occurred during this time. In 5.75 hours, the temperature was 23 C. The solution was clear. All coacervate had dissolved and there was no remaining odor of ethylene oxide.

Two hundred and 70 parts of water were distilled off to the point at which the reaction mixture became cloudy. This mixture separated into two layers on cooling, but in two days crystals started to form at the interface between layers and the mixture was accordingly stirred in an ice bath for seven hours. Thus, a large amount of crystals formed which were filtered off and washed and dried as usual, using ethanol and ether and a vacuum drier. The yield was 27% based on silica and 14% based on the ethylene oxide or morpholine.

This product had the molar ratio of morpholine complex:3.23SiO l2.1H O (lM O:0.58 morpholine complex oxide:3.23SiO :12.1H O). The crystals were semi-cubic and had the indices of refraction alpha=l.494, beta=l.498 and gamma=l.502. The recrystallized product melted at 62-64 C. but began to soften at about 55 C. It was quite soluble in water, but not in the usual organic solvents.

Example 8 V A sodium N,N,N',N' tetra- (2-hydroxyethyl)-piperazinium silicate was formed using N,N'-(2-di-hydroxyethyl)-piperazine. In this reaction, in the presence of the sodium silicate, ethylene oxide adds on to each nitrogen in the piperazine ring forming .a quaternary ethanol compound. Thus, it is a derivative of tetraethanolammonium hydroxide. in which two of the tetraethanolammonium hydroxy compounds are combined by the loss of 4CH OH.

'In this reaction, 70 parts of the piperazine compound was dissolved in 300 parts of water with 240 parts of E sodium silicate. A heavy coacervate formed, but the mixture was-treated as usual at 25-30 C. with 36 parts of ethylene oxide allowed to pass gradually into the reaction flask. In six minutes, the temperature had risen to 22.5

C. fro'm 2'1 'C., with an increase in coacervation. After SO-minutes, thetemperatu're was 27 C. inside the flask anda'llof theethylene oxide had been taken up. In one hour and 16 minutes, the temperature was 26.5 C. and the solution had become clear. In five hours, the temperature was 25 C. and the reaction was shut off and the flask left closed at room temperature overnight. There was no odor of ethylene oxide and crystals had formed on the bottom of the flask. On furtherrefrigeration, a large number of crystalsformed in a few hours. These were easily filtered and washed with ethanol and then washed twice with ether and dried in vacuo. The yield was about 7% based on the silica and 6.6% based on ethylene oxide or the piperazine. The mol ratio was 1Na O:2.2 quaternary complex:6.4SiO- :19.3H O. (The mole ratio for the oxide is the same as for the complex in this case.) These crystals were elongated plates being strongly birefringent and having the refractive indices alpha1=1.506, beta=1.5l2 and gamma=1.520. The crystals softened at about 104 C. and melted with decomposition at 110-111 C. They were fairly insoluble in water and quite insoluble in the usual organic solvents. This product contained an exceptionally low amount of Na O as shown below and by continued washing with water, the Na O content may be reduced below 1%.

I have also carried out essentially the same reaction starting with piperazine itself and forming ethanol groups by reaction with ethylene oxide. The final compound was the same.

Example 9 Sodium-N,N,N'-tris-beta-hydroxyethyl N tris- (betahydroxyethyl)-ethylammonium-piperazinium silicate was prepared using N-Z-aminoethyl-piperazine. This again may be considered a derivative of tetraethanolammonium hydroxide in the same sense as the previous piperazine but in this case an additional tetraethanolammonium compound is combined with one of the ring nitrogens.

Fifty parts of the piperazine were dissolved in 300 parts of water and mixed with 240 parts of E sodium silicate. This formed a clear solution which was treated at about 2530 C. as usual with 53 parts of ethylene oxide. After 8 minutes it had risen to 285 C. with a coacervate forming but refluxing as the ethylene oxide was slowly added. After 18 minutes the temperature had risen to 33 C. showing a very strong exothermic reaction which had to be cooled with ice. More coacervate formed but no refluxing occurred. After 25 minutes the temperature was down to 25 C. and a heavy coacervate was present. At this time cooling with water was all that was required. After one hour the temperature was 28 C. and no refluxing was occurring. All the ethylene oxide had been added and the coacervate was dissolving. In six hours the temperature was 25.5 C. and the solution was clear. This clear solution was left in the refrigerator at 2 C. overnight without further concentration. Since no crystals formed, an additional 53 parts of ethylene oxide were added. No refluxing and no coacervation occurred and the ethylene oxide was added in 1 hour and 10 minutes. The reaction was left for hours more, leaving a clear solution with a strongodor of ethylene oxide. No crystals formed when this solution cooled overnight. 173 parts of water were distilled off and the concentrated solution was again cooled. At this time a fairly large amount of irregular crystals formed which were easily filtered and washed twice with ethanol, twice with ether, and dried in vacuo.

The yield was 13.1% based on the silica and 15.8% based on either the ethylene oxide or the piperazine. The crystals had a mol ratio of 1Na O:1.3 quaternary complex ion:4.7SiO :ll.9H O (1Na O:1.9 quaternary ammonium complex oxide:4.7SiO 11.911 0). They were diamond shaped in habit and had refractive indices of alpha=1.502, beta: 1.512, gamma: 1.520.

The crystals softened at 55 C. and melted at 64-65 C. without decomposition. They dissolved readily in small amounts of water but not completely in larger amounts. They were insoluble in the usual organic solvents.

In the analysis of these crystals it is necessary to know which nitrogen compounds are titratable as Na O is calculated from the determination of nitrogen and total titratable alkali. Thus only two of the three nitrogens in the N-Z-amino-ethyl-piperazine can be titrated with HCl. In the other compounds all of the nitrogen was titratable.

Utility The utility of the compounds produced in accordance with this invention is exactly as set forth in my parent Pat. 3,239,549 (column 21, line 21 to column 22, line 21) and said patent is hereby incorporated herein by reference.

In this invention the ratio of the components is obviously controlled by the relationships established for X, Y and Z in the general formula.

Since results analogous to those indicated in the foregoing examples are obtained with other equivalent reactants, it is not intended to limit the invention to the details of the examples but only broadly as defined in the following claims.

What is claimed is:

1. A method of preparing compounds having the formula:

M O-X(N R O-YSiO -ZH O wherein:

M represents at least one alkali metal;

X is between about 0.5 and 1.5;

n indicates the number of nitrogen atoms and is a small integer less than 10;

R represents an organic radical that forms with N an NR base selected from the group consisting of alkylamines and alkanolamines, which produce solutions with a pH of at least 9;

p is equal to the number of R groups and is at least 4 and up to 4 n;

s is an integer from 1 to p indicating the number of different types of R groups;

Y is between 2 and 10;

Z is between 1 and 40;

which comprises reacting an alkylene oxide, an amine compound corresponding to NR, and an alkali metal silicate, crystallizing and recovering the crystallized product.

2. A method according to claim 1 wherein said amine compound is an alkanol amine.

3. The method of claim 2 wherein said alkanolamine is ethanolamine.

4. The method of claim 2 wherein said alkanolamine is triethanolamine.

5. The method of claim 2 wherein said alkanolamine is monoisopropanolamine.

6. The method of claim 2 wherein said alkanolamine is diethanolamine.

7. The method of claim 2 wherein said alkanolamine is tri-isopropanolamine.

8. The method according to claim 1 wherein said amine compound is an alkylamine.

11 12 9. The method of claim 8 wherein said alkylamine 3,326,910 6/1967 Weldes 260448.2 N X is ethylamine. 3,338,901 8/1967 Weldes 260-448.2 N X X 10. The method of claim 8 wherein said alkylamine 3,383,386 5/1968 Weldes 260 -4482 N is tetrahydroxyethyl ethylene diamine.

5 DANIEL E. WYMAN, Primary Examiner References Clted P. F. SHAVER, Assistant Examiner UNITED STATES PATENTS 3,239,521 3/1966 Weldes 260-448.2 N X US. Cl. X.R.

3,239,549 3/1966 Weldes 260-4482 N 260-247, 268 290 448-2 448-8 R I 

